One problem I've found with keeping currency is the rules on simulated IF. To log instrument hours means either flying in real IMC - which means seeking it out when there's perfectly good VMC around, not necessarily the safest option in your average flying school spamcan - or bringing another pilot along to act as safety pilot. In practice therefore I find it difficult to get enough IMC hours in without planning especially to do so.
On the question of that 'safety pilot': I've seen it quoted before that they have to be rated on type/class, but it doesn't say that in the ANO, at least not in the bit about simulated flight in IMC. Anyone know where the reference to qualifications is? I've got a couple of airline pilot friends who would make excellent safety pilots but neither has a current SEP rating.
Tim