AGM battery charging and PL20 advice

Good afternoon,
I was hoping that someone may be able to answer a few questions for me.

I have just changed over my wet cell batteries in my camper trailer to Remco agm (2 x 100amp) and would like to know the following.
I have both a Ctek 7 amp charger and a Xantrex truecharge 20i. From memory I have read somwhere that the Ctek may not be suitable for leaving on a float chartge with AGM's for an extended period of time?
Has anyone heard of this? Should AGMs be left on float for months or should they be charged and then removed from the charger?
On the the truecharge 20 there are several settings eg wet, gel and temp settings. Is anyone familar with this charger and which settings would you use when charging the remco batteries.
I'm not sure if the agms should be charged as wet or gel?
Finally I have a PL20 which I assume will need to be reconfigured for the AGM batteries if you are familar with the Pl20 which settings would you reccomend to charge these batteries?

Thanks
Chris.