Awesome thoughts and detailed account of your experience. Thanks very much, you write very, very well, I wouldn't have known English wasn't your first language mate.

I have suggested that this review be put on the main page to get more exposure. I think many people would enjoy your accounting.

Thanks for your kind words
When I first started this review I wouldn't thought that it would take so long and be so lengthy, but the more I listen to the I+ V5 combo, the happier I am. Never could imagine it would take less than $200 (90 for the I+ on Massdrop, 80 for Burson V5 SS; Voskhods, GE and EI Yugos all dirt cheap on ebay) to own such a wonderful-sounding amp combo.

No it's not possible to close the I+ with my Burson V5. That is, unless you also buy an extender cable from their site and try to shove everything in the chasis. It's possible, but I forgot to order the extender.
And yes I got it from their website. Thankfully, unlike other stuffs, shipping opamp to Vietnham has never brought me any problems at all.

Thanks for your great review of both this amp and the various tube/op-amp/headphone combinations that you've used. Through sharing your experiences, you help save me from having to spend time & money on things that are not optimal for the Little Dot.

I'm still trying to find someone who has the extender for the Burson V5 installed to see where and how they managed to fit it into the chassis.
I've also been thinking of possibly cutting a hole into the bottom cover and using some isolation cones or something to raise the chassis off the table top enough to clear the V5 in its direct connection mode.

Thanks again.

@Sdmark
My extender should be here any day now, I will also get the V5i at the same time. I'll share my thoughts and impressions from both in the LD I+ thread when I get the time. 
 
@WilliamLeonhart Great work!

@peter123 Thanks for sharing@peter123, that would be great. Some pics would also be helpful. I've already got some Voskhod tubes but I guess I'm going to get a couple of RTC 5643's and some of the EI's in addition to the Bursons. I just need a bottomless wallet. :/

@peter123 & @Sdmark thanks for your compliments, as this is my first English review your words mean a lot to me
I got the extender after this review and actually it is not a "cable" like I imagined before. It's still bendable, but so far I have not risked it yet. 
As for the V5i, I also got one already from Burson but I have not put it into the I+ yet. For the much smaller factor it certainly fits inside the I+ without any problem.

First off, this is an amzing review. I also had a question? Do you think this would pair well with a Sennheiser HD598? Thanks

Fantastic review and so well written, thanks. I have the Mk 2+, does anyone have any advice on opamp rolling? I have already gone with Mullard and Voskhod tubes, but I have not yet opened the case.