VU Clone have the following potential issues if your unlucky:
1. Reports of Poor Factory quality control meaning you can get a box with badly soldered front LCD.
2. Power Supplys weak, failing or DOA, more noticable with motorised dishes or 3.5" hard disks due to more power draw from the PSU.
3. Cannot run the latest images due to new VU driver protction.
4. Random "tune failed" when changing channels, apparently Ferarri team are aware of this and it's related to a query to the security chip failing update to fix this is due soon..
5. Remotes control response can be slow and laggy.
6. Fan can be noisy.
Of the above 6 issues the first two can cause you some grief and end up in you having to send the box back for repair or do a DIY replace of the PSU. The remaining 3 issues are nothing major, you can still use patched images and theres nothing significantly new in the later images yet anyway. Most Clone dreamboxes can run the latest drivers and images either without patching unless you have a AP82 SIM.
I have had a VU DUO V2 clone for a while now, and havent had any major issues, the box is stable, doesnt crash, all features work as they should. I replaced the Fan with a more silent Fractal fan. I do have the issue with random "tune failed" but it's intermittent.
All in all apaprently a VU DUO clone is only around 16-20 quid more than a 800SE clone so the benefits of dual tuner are definitely worth the extra cash..however this largely depends on recieving a good box without defects from factory in the first place !