Wireless (802.11n) is good for up to 108 Mb/sec, while 802.11g is good for up to 54Mb/sec. You won't lose anything going wireless. It is a small expenditure, considering the time and hassle factor of fishing Cat 5 cables through an existing wall, through the header, into the attic, down the other wall... It's something of a PITA if you have never done it before. We could coach you through it, but wireless would be a much better option in my opinion.