XS.com is a reliable broker for the long run. Reliability aspects are diffrent for everybody actually. For me i have a small brokers checklist, that they should have:
-Regulation (this broker has 5 regulations, which makes them globally regulated)
-Segregation of clients funds (so that our money are safe)
-Company insurance (5 mil by Lloyds of London)
Xs.com has a tick in every aspect for me, so now everithing depends on me regarding trading and making money.