14mm UWA and 2" barlows

I want to get a 2" Barlow to use with my Meade 14mm UWA, Nagler 11 T 1. Can I use a traditional barlow (TV Big barlow)or do I need to get the 2" Powermate? I know the 31 nagler will vignette with the Big Barlow but how about the 14mm and 11mm ultrawide/Nagler? Also will the eye relief be "thrown out" beyond the comfort zone with a traditional barlow? Assuming the Big Barlow won't vignette/encourage blackouts will I be giving up anything with regards to image quality versus the Powermate. Looking for someone who has had experience with 2" barlows/image amplifiers.

Thanks in advance,

David

I've used my 14mm UWA with a standard 2" Barlow that I got from University Optics without any problem - no vignetting. And the eye relief stays the same, it can't get "thrown" out.

I would have thought that the only times you'd strike noticeable vignetting problems was with low power 20 to 40mm eyepieces. And then, mainly with shorty type barlows.
Renato