Yeah, at the end of the day, they all transmit 0.5W and their antenna are very similar. You get some which manage a blim better reception by using a better chip managing the squelch/pre-amp interaction, but you're not really going to notice it unless you spend enough for XTNi / XTNiD sort of quality. The main difference between the sub £100 ones is bells & whistles which we, as airsofters, hardly ever, if ever, use. The cheaper and/or crapper ones suffer more and more from distortion, but it matters where the majority of it enters the system: in the amp stage is better b/c keeping the volume low increases the signal to noise ratio, whereas before that and it's there whatever you do - the thing is the pre-amp is part of the main chip, which is why Motorola have the edge when it comes to cheaper handsets - they brand their own chips.