We bought a 243RKS Cougar back in 2006. We loved the size, the layout, the light inside. It did take us 2 years to get all the design issues repaired and they were significant. Things like the black tank that leaked and clogged often or squealing brakes that finally took an independent shop to fix. Keystone was helpful but our dealer was clueless and inept. After we got it sorted, it was a very reliable and comfortable TT for us.
We looked at Northwood (Arctic Fox) at that same time and found them to be very well built albeit a little more pricey than the Cougar for comparable size. I thought it was because the Nortwoods were constructed for 4 season use but we found the interior to be a little claustrophobic due to small windows. The Cougar had much bigger windows and more of them. Where we camp (the Great Northwet) light was more important than insulation.
I am NOT a mechanic although I do play one in my garage!