If you really don't want refurb, then your other alternative is to build one using quality parts throughout. It will cost you a lot more though, but will be better than those mini pc's (and dare I say it even the Dells, but you're paying for it).
In the EU that might be a better choice as there's not the through put of nearly new pc's you get in the US. In the US, you should be able to pick up a nearly new Dell just fine as per Fenderman. The difference between EU and US is in the EU or UK at least, businesses don't get the bulk buy deals they do in the US where they buy more manchines than they want because it's cheaper than buying what they want, so you don't get sales of new surpless machines. Also, in the UK, businesses are tight and most will run machines into the ground, fixing them along the way until they can't be useful anymore before changing them. Believe me I've worked at big firms where you can make a cup of tea whilst your pc boots and still come back and find it only just starting. The result is in the UK there's not much supply of nearly new and used could be worn out even if "refurbed". Refurbed are also more expensive over here.