Very good in my experience- I've bought from them about 3 times now. Their postage is cheaper to Northern Ireland than the vast majority of GB-based shops, which makes them awesome in my book.
Only had one problem, my little vht special 6 combo which is faulty. I emailed them last night, they replied this morning with a prepaid return label. Don't want to jinx it, as obviously it's not completely sorted out yet, but my current assessment of them is "awesome- how internet transactions should work".
:)