I'm afraid I cannot comment on specific eqpt acquisition beyond what is available in public domain. Also I'll advise you not to extrapolate on the basis of one eqpt as that is likely to give you an incorrect and misleading picture.
What I've tried to correct is the notion that IA/IAF/IN has the authority to procure (including trialling) wpns & eqpt. They DO NOT have any authority to procure ANY eqpt, they follow the orders from the relevant Jt Secy in this case JS & AM (Land Systems). If there is anyone ultimately responsible for delays then the buck should stop at that person's desk. I cannot find Adm. Joshi's post-resignation interview where he shared that he didn't have any authority to even reorder new batteries for Kilos, this was reorder and not new eqpt acquisition.
You raised a pertinent point of product lifecycle management i.e. what will be rate of servicing, rate of replacement of key consumables, etc. Various trials are an empirical method of arriving at precisely that lifecycle management for each and every induction. Now you can see for yourself how many trials will be required, depending on the complexity of the eqpt. For some eqpt such information might be available from OEM, for others which are ab-initio development there is no short-cut but to conduct trials for the entire system and its sub-systems...sometimes together and sometimes independently or in various operating modes. Again all these trials, their reports and any requests for re-trials (sometimes there is fall-out between the trial teams comprising of various experts as not everyone agrees...say an EME officer might not agree with the maintainability of the electronics in high humidity of NE while the AD Arty member might think the radar will not perform as per spec for low-flying fast jets in built-up area, these might require re-testing so the eqpt has to go through another trial where those conditions might have to be created by asking for a unit to be taken to high humidity area like Gopalpur-on-sea or a flt of Jags to be requisitioned from IAF for revalidating).
Please don't get me wrong that OFB products go through trials over and above what is planned for other OEMs if they are competing in SAME trial. There have been very few occasions when OFB products have competed in a trial...maybe the recent vehicle trials come to my mind where it was a competitive trial, otherwise they generally don't compete. At the expense of generalising, the quality of OFB products are inconsistent, both at prototype stage and production-stage with lackadaisical approach to the entire process i.e. poor support during the trials, incorrect documentation, disappearing during trials to attend union-related functions, etc. Even DRDO gets nervous once they hand over their successfully development/prototype trialled product to OFB as then they are at the mercy of the OFB production processes. I'm hoping OFB are changing for the better as per media reports regarding recent Dhanush trials...hope the change becomes institutional.
Regarding your suggestion about an independent quality control agency...well that is what DGQA does http://www.dgqadefence.gov.in/toplink.php?id=15
. DGQA finds faults, stops shipment, OFB rejects their finding, delays to shipment, AOC or receiving unit questions where is my authorised strength, DGQA relents, shoddy eqpt lands in unit lines, now its IA/IAF/IN who are the evil, anti-national, Import loving somebody elses army/AF/navy for not being able to operationalise the eqpt. What they want is an eqpt that works when required, not a lines/hangar/dock queen. Now not only you have a problem that a unit is under-equipped, but that means that they cannot train their cadres, deploy in time, over-use the remaining eqpt which breaks down and lands up with OFB...net-net the import loving army/AF/navy gets blamed for delays in induction caused by others.
At the rate at which the blame-game is now going on, I don't think that day is too far away when IA/IAF/IN will come with folded hands to MoD mandarins and to jingoes like those in media and some over here on BRF and hand-over the command to them and say do as you please per your infinite wisdom.