Firstly they stock pretty much everything that a guitarist or drummer could ever want, with an ever increasing list of brands. They're also very helpful, both in email/phone conversations and in their actual store.
I've spent a fair bit with them over the years and they never seem to falter. Their loyalty card system is also pretty nice, you could easily rack up enough points for freebies if your a pro musician.
They've also started doing fairly informative reviews on YouTube. I know they're doing it to generate sales, but they do it with a fairly subtle touch.
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