The Bolzano is very similar to the PCA, so if you are getting that, defo get Trento. Trento has some nice "odd" setups that work better than what you would expect. I have got 60+k attack in Trento in Blitz many times. Bolzano is OK, good potential, but not as good as Trento if you investigate gun options.

And yes, I have levelled them both through Blitz this last week or so.

well i should say the Bolzano line is better why

1 Bolzano line has Capitani Romani that one is the small size CL u can use it with x1 5.5"/56 Skoda or 7.5"/39 Skoda ( i prefer to use single barrel gun cuz it much faster rld than dual gun and also have good dmg per shot) and due to her size u can easily battle  other CA use HE heavy shell to cuz more dmg per salvo don't worry  cpt romani size will help u to ur gun range

2. Bolzano is useful in GB cuz  her lvl is not much different from BB1 so if u don't like BB1 u can lvl with Bolzano equip her with single barrel 10"/40 EOC "R" or 12"/40 so now u are the mini BB ur gun number are same with BB1 but u will get better rld cuz of it's the single gun(BB1 main gun is dual it has more rld time with horrible spread on ur lvl that's why i prefer u to play Bolzano) i know trento have the same gun setup but due to lvl diffrent u will gain less exp if u want to skip BB1 with CA

These are short term lines to chose from and won't have much impact to you since you'll be out of blitz rather quickly and into GB2. I would suggest at BB level you go Regina Margherita line. Unless you have very good guners that are over leveled and have really good engys.

If this is the case take the Di Saint Bon route witch has smaller ships that can zoom around in BB2-6's lower ranges and they will still take ages to hit you because of the tiny hitbox. I was being shot at by 5 BB's at once (all the S bb's) and still managed to knock out 65k and a yammy while our H44 and monty hid in the corner.

Regina has more gun space and more of a gunboat where as the Di Saint line is more stick and move similar to a high level PCL lol. With 6-8k salvos (only 2 guns lowish reload).

Once you have the 1915 Ciao or Conte is pretty much nightmare for every BB out there. (44knts small ship spitting 13shells of 25degree lazer beams. Say NN armor, say NN DP) Rush sink someone rep rush sink someone rep. Repeat and enjoy 200-250k dmg per game. (60-80k exp average after double exp with prem)

I would recommend the Bolzano line:  leveling in the Capitani Romani is much easier due to its small size.  Just put on the 5.9"/45's, then sit back and snipe until the battle ends (500 damage with LHE too for some reason)...

bolzanao line.

capitani romani is the reason for this. dd sized cl with scout. nice dp, submergeance is amazing so it can take hits.

unlike the other posters i do not reccomend either of those guns, as they lack the potential that the six inch eoc singles do. use heavy he shells and deal massive damage with godlike penetration. it penetrates belt whored sirius as though they have no armor. last but not least, in great battles throw hedgehogs on the t slots, and the six inch eoc guns on r slots and hunt down those subs. underwater? use hh, when they surface unload on them with your guns, they do over a thousand damage per shell to subs.

and..that little cl at later levels can comfortably fit the ten inch singles on it. 

i chose bolzano line, haven't reach bolzano yet but love the capitani romani :D

I use 6" singles and goes around 45+knts and a fun aw set up, 13" belth with 6" singles full crew and goes 29/41knts lol

Ive Had Both. But I Deff Preffer Bolzano. Its Almost Unsinkable With 60 Bulge 3 in Belt Armor And 1.5 Deck With LvL 54 8 In Gunners

Bolzano is better..

Still, I using Capitani Romani all the time until I get BB3 for good ship..
It is very good support ship and main attack ship as from blitz. 
When my gunners are in good level, I can use EOR 10" singles in Capitani Romani for some reason and it is very bad OP when coming into the blitz room because it can smash any ships in seconds (If you have good accuracy and great reload). Not even PCA with BC guns won't stand a chance to against Capitani Romani arm with EOR 10" singles. (4 RM 10" single vs more than 4 11" guns - over)
It is include BB/PS/BC in blitz level with bad spreads. 

Beware, the shells in capitani romani with 10" EOR singles is limited.. You can only have 40 shells in use every battle.. 

The Romani line is way better. I've done both, and while Trento is very good, the other CA (forget what it's called.) is insane. I've seen it tear BB's to shreds. Regina Margherita is just going to die with that thing against it. I've seen as Vittorio Venetto get one shoted by this thing. =:O