Ok, well everyone keeps saying to stay clear of HDD cameras because editing the footage is such a pain. What exactly is/are the problem(s)?

anyone have a say on this?

I have a hard disc drive cam,only standard def,but i've never had problems editing footage from it.Plug it into usb on pc,pc sees cam as another drive,copy files across in seconds,into documents or whatever,remove cam,open editing program,import footage from where ever footage was placed,easy !!.

OK I'll bite. It uses a more lossy format than Mini-DV. Not really a problem if your editing consist mainly of straight cuts. Where it WILL show is if you start doing anything above and beyond. Transitions, compositing etc as the original source contains less information and is therefore subject to more incorrect interpretation.
Think of it this way. If you compress something and (deliberately) lose some information, then decompress it again, you get a first generation copy. If you recompress using EXACTLY the same algorithm and decompress again you will get no difference.
If, however, you make a change in the decompressed data and then recompress, you WILL get adifference.
It's different from analogue audio tapes where each generation adds noise/removes detail in that it will only add noise/remove detail if you make changes in between.
The other BIG disadvantage of HDD is you will copy it to you PC and free up the space on you camera, work on it and delete it. Then, a while down the line you want a clip form it but you've got no source to work from. (Unless, of course, you're VERY disciplined)

__________________
Tim

so is this reduction in video quality only noticeable to the trained eye, or would i not even notice too much and the quality would still look phenomenal compared to SD?

As usual "it all depends".
As I understand it, so long as maintain the same format throughout the process:
There will be no degradation if you perform straight cuts only.
If you perform dissolves, then the source has to be decompressed, the effect (ie the dissolve) applied to the uncompressed footage, and then recompressed.

The more you decompress and recompress, the more "errors" are introduced.

I suspect that unless you have effects or multiple layers with different levels of opacity, you won't notice the difference.

__________________
Tim