One Pro to the TRX-2 would be the ability to decode NXDN out of the box. Not sure how much NXDN is in your area of PA though. I have found that there is not much NXDN being used yet in the Northampton County area. What NXDN we do have sounds great though. Decode very good even on weak signals. Same with DMR actually.
Although I haven't experienced this myself, I have read that the TRX series suffers from the same simulcast distortion as the Unidens. Some say this distortion is better, some say it's about the same. I'm far enough away from simulcast systems (Bucks/Berks) it really doesn't cause me problems.
I can't speak for analog except trunked. I don't listen to any analog conventional with either scanner. I do listen to Motorola and LTR analog trunked systems and they sound very good.
I have noticed that the TRX-1 and TRX-2 do not suffer from front end overload as some of the earlier GRE and Whistler scanners have.
Another Pro for the Whistler would be the customer support. Whistler has been excellent IMHO supporting the product after the sale. They have also taken suggestions for added features and have made some a reality to date.