Willby - it could be that the Irish version is more expensive because it is specific to the RoI. The DMR-E55EB is the UK model and has a tuner covering UHF Ch 21-68 plus an RF output converter also covering UHF Ch 21-68. However, the RoI model is the DMR-E55EBL which has a different tuner covering VHF Ch4-13 and A-J, plus UHF Ch 21-68 but no RF output converter. So you cannot play DVDs back through an RF connection with the Irish model, I guess....unless you connect an external RF modulator to the AV3 output on the back of the DVD recorder.
Regarding using Sky Personal Planner, the only problem with that is that you cannot record in RGB using it, you would only be able to record composite output. If you want to record RGB from Sky, you have to leave the satellite receiver switched ON (not just in standby) and on the right channel until the time of the programme you want the DVD recorder to record... The only way round this is to use some external timer to switch the Sky receiver from standby just before the programme you want to record. I use the (now sadly discontinued) Panasonic NJ-FJ710B VCR for that purpose because it has the brilliantly simple 'Intelligent Satellite Control' system which allows it to emulate a Sky remote control; a few moments before a timer-set programme is due it wakes up, brings the satellite receiver out of standby and onto the pre-programmed channel by firing an IR command, then starts the VCR. The Sky receiver just 'thinks' that the normal remote control has been used! So I use that to switch the Sky receiver on, then use the RGB output for recording on the DVD recorder. I just have to remember to put a tape in the VCR otherwise it'll stop everything when it comes to the end of the tape.
The RF loopthrough on the UK model is useful for piping DVD pictures through to a kitchen TV using an RF daisy chain - and before anyone asks, no, it doesn't inhibit Macrovision, so you can't make pirate copies of pre-recorded DVDs for your mates by taping the RF on a normal VCR - or second DVD recorder!