The Genesis MRL ACe's were a 2010 release of the pre-insulated cab version, starting with Road# 4301 (4 #'s). MTH released 2, 4304 & 4308. I've been told Kato also did some. Whether any more in the 4300-4315 series will get released is probably doubtful. MRL have now got about 6 of the new insulated cab series which start with #4400. Hopefully Genesis will announce a new model of this prototype soon. Considering the competition there is on US-ebay for anything MRL, with prices going well above original retail, they'll take notice and do at least another 4. I have 2 Gen 4301's as I have mentioned somewhere, there was a 4313 in Canada, wouldn't do international shipping, and 2 of the 4304 MTH's, so a bit of renumbering needed. Will only consider more MTH's if they're the DCC ready ones.
The main spotting feature for the insulated cabs is a vertical joint line just behind the nose that continues over the top and another near the cab base (horizontal) and then up at about a 45Deg angle. The last of the real F45's, 390 & 392 have just been retired. Both were slated for scrapping, 392 is no more but 390 has received a last minute reprieve and rumoured to have been sold to possibly a museum or tourist line. It was their only GN original and apparently also had updated control systems. There'll be a rush on that # if Athearn cotton on.
Almost all of their remaining SD45's have also been scrapped since the introduction of these latest ACe's. Going by the new roster on the Yahoo group, only 2 remain. It is a bit confusing because they had/have both 45's and 45-2's as you would expect them to appear, but many of the 45's with their flared radiators had been rebuilt to -2 status and are listed in the roster as such, but of course don't look like -2's. They also have done the same with their SD40's but do have 1 genuine SD40-2 (#250) which has been modelled in both bluebox and as I discovered last night on US ebay, in the upgraded RTR, Kato have done the SD-40's. MRL still runs GP & SD9's (some modified designated 19-1's), SW switchers (9, 1200 & 1500), GP35's & SD35's.