Dear Sprunger:
Now I'm amid the joy of building a 1/48 Su-15TM from Trumpeter. It' my second experience with Trumpeter and I have to admit that it does very, very well.
Don't let be mistaken. Even Chinese, it's a very good one. The pieces plastic frames are rustic, maybe, but pieces themselves are very good. They fit very well and I have saved lots of putty.
There's only a sole, big and significant error in design. The radome is straight ahead the cockpit and the real aircraft has a very slight inclination downwards. Don't worry. Other modellers around the world have found a solution by sanding or cutting the lower portion of the fuselage just in the place it fits with the radome, by exactly 3.4 millimeters and everything gets fine! I'll send to you a drawing I found via internet.
I have purchased the Part (TM) modification kit with photoetched parts and if you're fanatic with very small details (I mean to build up microscopic wheel bay doors hinges, for example), I recommend it to you. But even if you leave them aside, there are many bigger improving parts (As the wing fences or the wheel hub lids) that fit incredible well. Furthermomore I recommend to you to buy the Su-15 Neomega (TM) resin cockpit if you want to let your bird with open cockpit, for it's real gorgeous. The only part that is somehow out of scale in this set is the radar visor but it's enough to sand a little bit (say around 1.5 mm) by its lower face and it will fit O.K.
I chose the metallic finish and to do so, I picked up ALCLAD II metallizer lacquers. They are the best I have ever used to get plastic into metallic. There's a wide range of tones but be sure first to use the correct paint base (enamel or acryllic, according to the specific type of lacquer tone). Read well first. I also reccomend to you to read the experience of Ingo Degenhardt in internet about this plane. Use a search engine (i.e. Google) and type Ingo+Degenhardt+Su-15
Concluding, Build it up!