I've got a Clarke lift with the hydraulic and pneumatic operation and it's great. I did have a seal leak so needed to replace it but the repair kit was cheap enough and it has seen a lot of use.
I really don't know how I managed before, especially doing front cylinder exhaust valve adjustments and, IMO it's worth paying the extra for the air lifting option as it is slow to lift by the pedal.
I altered it slightly by 'widening' the wheel chock so that I can clamp the rear wheel as this gives another option for removing the front end etc. plus you can remove the clamp to get the bike on paddock stands for tyre changing etc. without doing your back in.
Takes up a lot of space but I use it as a parking space for 1 bike when not in active service.
Also comes in handy for lawnmowers, quads etc. - highly recommended.