Definitely Suncoast
Having within the past month driven two vehicles that have been switched from stock over to a Suncoast custom billet converter, and having dealt with Ron Wolverton of Suncoast directly, my opinion may be biased but I'd definitely say go with Suncoast.
If you go over to
L. O. S. T KJs Offical Web Site - For Jeep Liberty KJ Owners forum, under the CRD section, you'll find an 18 page thread on finding an Aftermarket TC for the Jeep Liberty CRD (started by yours truly). DC put a 545RFE transmission behind that four banger 2. 8L turbo diesel, and then stuck a gas engine torque converter with a 2300 rpm stall speed in between. Small wonder when a lot of those TC's started directing their nipples skyward. DC's answer was the F37 "Customer Satisfaction Notice" - they basically just swap out your old stock POS TC and put in a new stock POS TC and then detune the hp/torque on the engine by 5 to 10 percent. "Customer Satisfaction" my *****.
Several of us CRD owners said no thanks to having our engines neutered (I've driven one that had F37 done to it, and it was a dog compared to mine with the earlier software). Warranty be hanged, we were going to find our own solution.
About this time, a gent from TS Performance in KY that owned a CRD gave it to Suncoast for upwards of two months specifically to develop a custom TC for it. The gent from TSP was also dissatisfied with the stock TC, and asked Ron Wolverton at Suncoast if he could come up with something better.
Only thing I can say is, Ron did one heck of a job. The "dog" I mentioned above that had already had F37 done to it was the first CRD locally to get the Suncoast TC, a Transgo shift kit, and new design oil pump (same pump that goes in the 68RE). It was an entirely different vehicle afterwards, more than made up for the software "neutering", and could eat mine for lunch off the line. To boot, a month later the gent that owns it tells me he now consistently averages 2 to 4 MPG more per tank than he did before the install, and that's hand calculated not EVIC.
Second CRD was an '06 with factory traction control and an aftermarket "economy" tune that added 20 HP/50 ft lb torque. Turned that beast into a 4300 lb hot rod. Even with traction control, you could feel the rear tires floating around when you nailed it from a standing start. You could audibly hear the engine load down when you put it in gear, and just laying your foot on the pedal was enough to get you accelerating at a good clip.
On both vehicles, it eliminated the engine and driveline vibration thats seemingly common to these beasts. Where before you could watch the plastic noise cover on the engine vibrating like a paint shaker, afterwards I was hard pressed to see any movement at all, and both rode as smooth as the '87 MB 300D sedan I have.
IMHO, the people at Suncoast certainly believe in giving a customer their money's worth. They do all their own work in house, and from what I've been related, they won't offer a product for sale unless they've been able to test it themselves in an on-road vehicle. They've certainly sold me with their CRD TC, and in two weeks I'm having one put in my CRD.