I have already posted this exact reply on another thread. But it may be of some use to you.
Just been through this exact thing myself. I was convinced looking online a hikmicro LE10 was going to be good enough for what I wanted. Went into my local sportsman gun centre and got my hands on a LH15, LH19 and a LH35. I was so disappointed with the image of the 15 the 10 wpukd be uselessfor anythingmore than a rat at 10 yards in my mind, the 19 was much better but the 35 just made a world of difference, it was like standarddefinition tv and hd the 19 and 35. I had set myself a bugget of no more than 600 quid, however that was immediately clear it wasn't enough. So was heading for the 19 at 899, but decided the 35 was so much better it was worth the extra and they gave me a cracking deal so left with the 35 and spent way more than I had expected but its worth the extra! Its a night and day difference between 600 quid thermal and a 1000 plus thermal. Been using it a couple weeks now and its a game charger. Just can't believe what iv been missing right infront of me