A question for those living in Great Britain

DH and I have been talking about taking the kids over to visit friends in Lincolnshire (Mablethorpe) next year.  I'm hoping to be licensed in the next month or two, so we were tentatively looking at the option of getting the ferry over and then driving rather than flying. I'm dying for a bit of a road trip. Our route options are Belfast--> Stranraer or Dublin--> Holyhead.  A quick look at the map and it seems like going to Holyhead would get us closer to our final destination than Stranraer would, but since I've never been off this wee feckin island, I have no idea how long approximately it would take us to get from Holyhead to Lincolnshire.  Any estimates?

Also, just for kicks, how long would it take to go from Stranraer to Lincolnshire?  Just trying to get an idea for both routes, since on this end it would take us 4 hours to get to Dublin just to catch the ferry!

Tim lives 6 miles north of Lincoln and when he came to meet me at Holyhead it took him 4 and a half hours because he got stuck in traffic on the Pennines, but it should have only taken him 3.  I think it took us about an hour to get over to Mablethorpe the day we went to the seal sanctuary, so I would say you're looking at 4-5 hours. 

However, trying to do it by train?  Would take over 7 hours to get to Lincoln and involve 5 transfers.  And this is AFTER you take the 3 hour ferry ride!

I think it took us about an hour to get over to Mablethorpe the day we went to the seal sanctuary

That sounds about right.  I used to live in Sutton-on-Sea (about 2 miles down the coast from Mablethorpe), and it was just over an hour's drive into central Lincoln.

Unfortunately, east-west routes across the middle part of the country can be slower and involve more changes from one road to another than north-south routes or east-west in other parts.  If you head onto the more northerly route you could use the motorways across most of Yorkshire, then drop down into Lincolnshire and approach Mablethorpe from the north.  The more direct route would take you nearer to Sheffield and bring you in from Lincoln direction, probably saving about 30 or 40 miles, but it will involve more jumping one from A-road to another on the way across, so probably wouldn't save much, if anything, in time. 

Thank you guys!  That really helps a lot.