And here's an article by Alan Haigh.
"Harrow Sweet, perfect home orchard pear
alan haigh October 19, 2011
Of course I can only speak for the region I grow Harrow Sweet and from much too little experience with it. This was the first year I've gotten a substantial crop from Harrow sweet, both from some grafts I put on another variety and a tree of only this variety.
OK, nothings perfect, but, so far, Harrow Sweet comes as close as any pear I grow. It is very sweet, which in our more northern latitude can be a major issue where pears often get inadequate sugar. The Highlands are as sweet as Seckels this year- the sweetest pear commonly grown here.
It resists psyla and scab which I can't say for Seckel and especially Bosc.
It resists fire blight more than the varieties most widely grown here- Seckel, Bosc, and Bartlett.
It ripens in Oct when high sugar, low acid fruit is really nice as stone fruit is pretty much done except maybe the last of the prune plums. It also means you can probably store them into winter.
It can be allowed to ripen on the tree. This is always an advantage for home growers trying to figure out when to pick. Seckel and Bosc also hold their texture and don't rot in the center when allowed to tree ripen there. Like Bosc, Highland turns golden when hard ripe so you can wait until then to pick them for storage and be assured optimum sweetness.
It is less attractive to stinkbugs than Seckel- at least so far, and because the tree I grafted it onto was a Seckel I literally got a side by side comparison.
It is a pretty tree with nice spreading branches. It also seems fairly precocious for a pear."
