Welcome to IRV2. You will learn a lot from this website, I know that I have. The owners forums allow you to research different brands.
Newmar makes similar gas coaches in the same class as the Allegro(Tiffin). We have a BayStar 3002 and are very happy with it. There's also a lower featured Bay Star Sport and an a higher end Canyon Star.
If you get a chance, take the factory tours that are available for the coaches that you are interested in.
Tiffins has a very good reputation also.
2013 Newmar Bay Star 3002 - 2004 Toyota Tacoma
Options: 5 Star Tune, Bilstein Comfitrac Shocks, Bilstein Steering Stabilizer, Blue OX TigerTrac, CHF, RVIbrake2, Centramatics Balancers