Sorry you have not got many replies as I am thinking of replacing my 4 year old oil boiler to a condensing one and looking for views.
My installer says it will cost about 1800 euro to buy the boiler. Install after that. Will allow me something on my old one. Says the new one could save me 30% on oil. He would not recommend wood pelletts and has taken a couple out as people were not pleased. Problem with supply, can get damp and storage issues. Also store which sells them tells me sales of them have dropped greatly.
I regretted not going for Geotherm. Have tiles on a lot of floors and it would have worked well, retaining heat, but was planning a bit before advancements in Geotherm. My builder has it in his own new house, mansion, and swears by it. Very economical and runs the pumps at night on low rate electricity.