I found anything with steel on steel is the best for crimpers. Flails on the other hand supposedly give you a day less on drying. I haven't tried them myself just because they shred green feed heads. With that being said, it seems no matter what setup you use you will still need that extra day before the rain:52:

 

We run a case dc 163 although it's 16' they make a 13'. We use rubber rollers. They are adjustable for both pressure and gap spacing.

 

Flails make for the quickest drying, but if it gets rained on when almost dry, hay really gets messed up, much worse than rolls of anykind.
I find any conditioner will knock apart greenfeed, I never see any reason to run it thru one, so don't.
Run NH Speedrowers for years with the rubber chevron rolls back in the days of the narrow crimpers, found them somewhat ineffective in heavy conditions, but once they went to the wider rolls in the big headers 14-18 footers for both selfpropelled and hydroswings, very noticable diff in amount crushed and better dry down.
Still have a 1475 with a 16ft 2300 series on it, haven't used it in years. Been cutting with 18ft Mulitcrop with 60 inch steel intermeshing rolls on my Macdon, its as good or even better than the NH with the wide rolls. As Beerwiser said, pretty hard to beat the steel.
Even the old ones were good, I grew up on a 16 ft Owatonna Imperial 81 with steel rolls in the crimper, those were the queens of swathers back then, sure didn't have the capacity or comfort we do today is all I'll say

 

We run a JD 995 on a r450 power unit. It has steel fluted conditioners. We cut 100 acres of alfalfa on Monday and it would've baled today if the tractor running the baler hadn't blown a front tire!

In my experience the past few years, the likely way for the absolute quickest dry down would be small cutting heads with conditioners as wide as possible merged a day or two later into a swath big enough to be a good fit for whatever baler will be picking it up. We have been considering a triple mower for that reason. Started using a phiber merger this year and it does work well....

 

I built my own. JD 1460 used to have urethane on urethane. They were worn out and missing large sections. Stripped it off, and welded 1" square tubing on 2 1/4" spacings to both rollers. Staggered in four segments. Run them very tight and it crimps the stems completely every 1/1/4" Stems are dry before leaves. lay out a wide swath, V rake together when dry half way through. I've baled 3 to 4 bale/acre alfalfa/timothy hay the day after cutting, two days is very common. Neighbors all think I've lost my mind when they see that. Always a day less than neighbors with factory rollers or impellers.

 

Do you have any pictures? Sounds like a good conversion. Did you have any issue with warpage on the rolls?

Have a set of rubber rolls on a NH 419 that are getting pretty rounded off and down to the steel in spots.

 

Nice jvw. I had a IH 1590 with rubber rollers that were almost smooth. I was very tempted to do the same, I was just concerned with balance. Did you have any problems with balance? Sort of wish I kept it now.

 

Hay Equipment Manufacturer | Hermiston

Was talking to a fellow this spring that uses these and swears by them. Circle C ,not cheap but he is growing Timothy and said they shorten up drying time . Considering them ourselves just not sure if our old discbine should be totally replaced or these put in.

 

No issues with warpage, welded in short segments, not full length. Balance may not be perfect, but compared to having half the rubber missing, it is much better. It is however very noisy when empty. Too much wear in the slip joints and drives, so the bars contact each other. In hindsight, wish I had started with a machine that wasn't already worn out, as it was a lot of work, and am committed to keeping this worn out machine going now.

I built the first roller outside of the machine, then installed both rollers and welded the bars on the second one inside, to ensure they were timed exactly. I'll takes some pictures.

I'm not sure why OEM's don't build something this agressive? What is the potential downside?

It also takes a lot more HP to run now.

 

There are these guys which I was going to order replacements for the 1590, less than half of IH price.
Weyburn Machining & welding shop | replacement augers | haybine conditioning rollers | M & R Machines Ltd
As Dan said, pics would nice to see.

 

There prices are half of what an oem replacement rollers are on mine. ...wish I knew about these guys a 5 years ago.

 

Looked at this 10ft massey/hesston the other day with steel on steel. Looks alright but they want $36k and that's a little 10ft side pull model center pull unit is more yet! Thinking of getting demo to just make a round beside mine and just see the differance. As a day or even 1/2 a day gain is huge when making horse feed and beating a shower.

Second pic is my TiCor rollers on the New Idea 5209 which I've replace the rollers once already as the originals got gaps worn in them on spots where the hay lands from the discs.