The TF 270 heads with roller springs and Ti retainers are $2600/pr.

I've had 4 sets of the 240 heads in the shop so far, and the overall fit and finish was very consistent.
They all had the guide clearance quite a bit tighter than what I prefer, and the seals are on super tight, so you can't get them off(or at least I don't seem to be able to) without ruining them.
So, IMO, the "prep" for the TF heads is to disassemble, hone guides, clean everything, verify spring pressures and installed heights, reassemble with new seals.
The roller springs that come on the TF heads(TFS-16318) are almost $340...... So you're getting pretty good parts there.

If you can buy the EZ295 for the same price as the TF 270, it comes with flat tappet cam single springs, steel retainers, 7 deg stamped locks, and umbrella seals.
If you buy the upgrades from Indy to get the heads so they are "similarly equipped"(k-950 springs, Ti retainers, 10deg locks, viton seals)to the TF 270's, it's going to add about $500 to the cost.
Then, if you really want them to perform like they should, the valve seats should be recut, valves back cut, and the bowls and chambers blended to the seats.
Then, again you have cleaning, checking spring pressures, installed heights, assembly, etc......... All of which adds up to another $500.
If you wanted spring cups, it adds another $100, and you'll also need the oil line kit for $55.

While i feel those two heads are pretty comparable, the place where the TF head really starts to look attractive is....... The price.