What do you mean by "too good?" I would grade it gVF. It's a very handsome coin to be sure, but Romans can get much sharper than that. Just because a coin is ancient doesn't mean that it can't look like it just fell out of the dies. Everything depends on how it was struck and what sort of conditions it had to endure over time.
http://www.acsearch.info/search.htm...&it=1&es=1&ot=1¤cy=usd&order=0&company= To answer a question like this, lets go to acsearch above and search for similar coins. There are many about equal and a few nicer. There are many under the price and a few over. From the research, I'd say that it is a nice coin but not worth that price to me. For the price, I'd prefer one with a bit nicer surfaces on the reverse especially. I do not have that type but yours is nicer than my three sestertii of Alexander which were $33 to $49 each (about $125 for all three). That would tend to suggest it is not a bad buy.
Some in your search are just stunning! Thanks for the help. I'm new to ancients but real excited about them.
SEVERUS ALEXANDER AE Sestertius OBVERSE: IMP CAES M AVR SEV ALEXANDER AVG, laureate, draped bust right, seen from the back ALEXANDROC AV, laureate, draped and cuirassed bust right REVERSE: PONTIF MAX TR P II COS P P S-C, Pax seated left, holding branch and sceptre Struck at Rome, 223 AD 17g, 26mm RIC 402
Roman Imperial Coinage: "a British catalogue of Roman Imperial currency, from the time of the Battle of Actium (31 BC) to the Late Antiquity in 491 AD. It is the result of several decades of work, from 1923 to 1994, and a successor to the previous 8-volume catalogue compiled by the numismatist Henry Cohen in the 19th Century. It is the standard work for numismatic identification of coinage struck by authorization of Roman emperors."