I've been looking to buy waves with BTC but all the websites i've found so far have mixed reviews so i'm not sure if i should use them..
Please let me know what website you use for buying and selling altcoins
Try to use Poloniex exchange they're user friendly and you can file a ticket if you have a problem with their site and you can use 2FA security to prevent from hacking or use Bittrext if you want a unique style and fast website, These 2 exchange site i've been using about a year now but the only thing i've experienced in poloniex is in withdrawal problem they are slow in approving a Withdrawal request but it is good to prevent from hijacking your bitcoins, They reviewing the withdrawal request before they approve it.
I would use Bittrex rather than Poloniex because Poloniex received some pretty bad reviews lately.
Bittrex also has other altcoins so if you really wanted to purchase something with your Bitcoin then you would have a lot to choose from.
Poloniex was a nice place to trade though the website is a little off now since they decided to close the trollbox on there. Poloniex does have a pretty good customer support when it works.